In a typical cellular communications system, a certain geographical area is divided into regions called cells. The mobile stations (MSs) in each cell are served by a single base station (BS). A BS transmits information to a particular MS (or a group of MSs) in its cell on the radio path referred to as the downlink (DL), while the MSs transmit information to the BS on the radio path referred to as the uplink (UL). The transmissions on the UL and the DL may be on the same time intervals but on different frequency bands (referred to as frequency division duplexing, or FDD), or on the same frequency band but during non-overlapping time intervals (referred to as time division duplexing, or TDD).